如何捕获包装在一对自定义Blade指令中的内容？

use Illuminate\Support\Facades\Blade;

public function boot()
{
    Blade::directive('capture', function ($expression) {
        return "<?php ob_start(); ?>";
    });

    Blade::directive('endcapture', function ($expression) {
        return "<?php \$__capturedContent = ob_get_clean(); echo \$__capturedContent; ?>";
    });
}

@capture
    <div>
        This content will be captured.
    </div>
@endcapture

<div>
    Captured Content: {{ $__capturedContent }}
</div>